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Old   March 9, 2006, 04:16
Default About convergence
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EA
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I tried to run the same case file in single and double precision solver. The convergence limit is 1E-5. The double precision converges while the single one does not. Why this is so?
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Old   March 9, 2006, 13:19
Default Re: About convergence
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Evan Rosenbaum
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Numeric diffussion.
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Old   March 10, 2006, 00:59
Default Re: About convergence
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EA
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Then how can I avoid this? Thanks.
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Old   March 10, 2006, 13:36
Default Re: About convergence
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Evan Rosenbaum
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Using the double precision solver obviously works. If you are using second order upwind try switching to first order, which is less susceptible to numeric diffusion.
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Old   March 11, 2006, 00:19
Default Re: About convergence
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EA
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I'm using QUICK scheme now. I will try 1st order upwind. Thank you!
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